Aromatic compounds and their manufacture

ABSTRACT

Compounds of Formula I or Formula II ##STR1## where A is an electron withdrawing group and B is a secondary or tertiary amino group or the group OD where D is H, aryl or an aliphatic group are made by reacting a corresponding compound of Formula Ia or Formula IIa ##STR2## in a solvent with a reagent selected from organic primary and secondary amines and compounds of the formula MOD where M is an alkali metal and A and D are as defined above. In this process the nitro group and the group B in Formula I and Ia are in the 2- or 4- position and the compounds of Formula I, Ia, II and IIa may optionally be further substituted. Preferably a primary or secondary amine is reacted with a compound of formula Ia, preferably using dimethylformamide as solvent. The process can result in the production of novel compounds, including (1) Compounds of Formula III  wherein each group A is CO 2  H or an alkali metal, amine or ammonium salt thereof or the two groups A together form a carboxylic anhydride group and B is in the 2- or 4-position and is OD, where D is hydrogen or an aliphatic group or is a secondary or tertiary amine group, (2) compounds of Formula IV ##STR3## where B is the group OD or the group NR 2  R 3  and wherein at least one of R 1  and D or at least one of R 1 , R 2  and R 3  comprise a solubilizing group containing a primary amino, carboxylic, sulphonate or phosphate ester group in the form of an alkali metal, amine or ammonium salt or is a polyalkylene oxide group, the compounds optionally being further substituted.

This invention relates to the production of polycyclic aromaticcompounds, and to novel compounds so produced, and especially to suchcompounds substituted by secondary or tertiary amine, hydroxyl or ethergroups. The polycyclic system is preferably a naphthalene ring. Suchcompounds have various uses, for instance as dyes, especiallyfluorescent dyes, as pharmaceuticals (for instance as anti-malarials),and as intermediates for either. The polycyclic ring can be ananthraquinone ring, the compounds then being useful as dyes or dyeintermediates.

The synthesis of many aromatic secondary or tertiary amines can berather difficult to carry out in an economic manner. For instance theproduction of a compound such as 4-n-butylaminoN-n-butylnaphthyl-1,8-imide may involve forming 4-bromo naphthalicanhydride and then reacting this with n-butylamine to form the desiredcompound, but this suffers from the disadvantages that it is amultistage process, it is difficult to make the bromo compound in goodyield, and the use of a bromo derivative necessarily incurs considerableexpense.

It is known to make some aromatic amino compounds starting from thecorresponding aromatic nitro compound but the methods of conversionagain are not entirely satisfactory. Thus while primary amino compoundscan often be produced simply by catalytic or chemical reduction, if asecondary or other amino compound is required then the primary aminocompound has to be subjected to subsequent reaction, such as with analkyl halide. In theory a secondary amine can be made in a single stageby reacting the nitro compound with ammonia and an aldehyde and hydrogenand a catalyst under pressure but in practice a mixture of secondary andtertiary amines tends to be produced.

Several processes are known for converting certain nitro-anthraquinonesto primary amino anthraquinones. Thus certain nitro anthraquinones canbe converted to amino anthraquinones by reaction with sodium sulphitebut again the synthesis is not very reliable and only forms a primaryamino group.

In British Patent Specification No. 1,524,729 several processes ofreducing nitro group in nitroanthraquinones to primary amino group arediscussed, and in particular a process is described in which a dinitroanthraquinone is converted to a mono-nitro mono-amino anthraquinone byreaction at a temperature of above 60° C. with ammonia in a dipolaraprotic solvent. It is explained in the specification that the reactiontemperature is preferably 100° to 130° C. and that the reaction ispreferably conducted by bubbling gaseous ammonia into the solution ofdinitro anthraquinone until a total amount of ammonia of up to 50%excess based on the stoichiometric amount has been introduced. Forinstance in Example 1 complete reaction is said to be achieved after 6or 7 hours at 120° C. In all the examples a mixture of reaction productsis obtained in which the main component is the mono-amino mono-nitrocompound. This suggests that one of the nitro groups is activated, forthe purposes of the reaction, by the other nitro group.

Whatever the mechanism however the process is restricted to startingwith dinitro anthraquinone, it introduces only a primary amine group,and always yields a mixture of products that have to be separated bywhat is, in practice, a difficult separation technique. Accordingly theprocess is of no assistance to us in our objective of devising a simplesynthesis for the successful economic and easy production of polycyclicaromatic secondary or tertiary amines. It is also our objective toproduce other polycyclic aromatic compounds, such as those containinghydroxy or alkoxy substituents.

We have now discovered a new process that appears to be conducted by areaction mechanism different from any mechanism previously described inthe literature for polycyclic aromatic compounds and which is applicablefor the production of secondary and tertiary amines, alcohols andalkoxides of naphthalene compounds and also of anthraquinone compounds.

The compounds produced by the process of the invention are compounds ofFormulae I or II ##STR4## where A is an electron withdrawing group and Bis a secondary or tertiary amino group or the group OD where D is H,aryl or aliphatic. B is in the 2- or 4-position in the compounds ofFormula I and is generally in the 1-position in the compounds of FormulaII, although it may be elsewhere, for instance the 2, 4, 5 or 8positions. The compounds may contain additional substituents. Thus thecompound of Formula I may contain, for instance, substituents A at boththe 1- and 8-positions and the compounds of Formula II may contain asubstituent B in each end ring and any of the rings may contain optionalfurther substituents as described in more detail below.

In the invention these compounds are produced by a process comprisingreacting a corresponding compound of the Formula Ia or IIa ##STR5## in asolvent with a reagent selected from organic amines and compounds of theformula MOD where M is an alkali metal and A and D are as defined aboveand the nitro group is in the position to be occupied by the group B inthe end product.

The reaction can conveniently be looked upon as a nucleophilicsubstitution since it seems to be controlled by the same parameters ascontrol nucleophilic substitutions. However we are not limited to thereaction necessarily being a true nucleophilic substitution reaction andthe reaction may involve, for instance, the formation of an intermediatecarbanion.

The reaction is carried out in the liquid phase preferably in thepresence of an inert aprotic solvent with the reactants in solution. Theaprotic solvent may be used alone or part of the liquid phase may beprovided using excess of the reagent (e.g. using more than 5 molesreagent per mole nitro compound) or a mixture may be used of aproticsolvent and other solvent that is inert to the reactants. Generally atleast half the solvent is aprotic and preferably substantially all isaprotic. Mixtures of aprotic solvents may be used. The aprotic solventor solvent mixture must be inert to the reactants and the desiredcompound. Solvents can be selected from tetrahydrofuran, glycol ethers,dimethylsulphoxide (DMS0), N-methylpyrrolidone, sulpholane,hexamethylphosphoric triamide, nitrobenzene and ortho-dichlorobenzene.The preferred solvent for reaction with amines is dimethylformamide(DMF), for purity, yield and convenience reasons. DMF and other amidesolvents, and solvents such as DMSO, are not inert to some compounds MODand when the reactant is MOD the solvent is preferably an ether, forinstance a glycol ether preferably the dimethyl ether of ethylene glycol(Diglyme).

The reaction medium should be substantially anhydrous and the reactionshould be carried out in the substantial absence of air, oxygen or otheroxidising gas. Preferably the reaction is carried out under nitrogen orother inert gas. For instance the reaction vessel and mixture may bepurged with nitrogen and the reaction then carried out under anatmosphere of inert gas. Preferably the reaction is carried out at orslightly above atmospheric pressure, e.g. 1 to 2 atmospheres.

The amount of amine or other reagent should be at least thestoichiometric amount required for reaction with the nitro and, ifappropriate, with any other substituents in the ring. Generally theamount is more than the stoichiometric amount. Preferably the amount ofamine or other reagent is at least twice the stoichiometric amountrequired, e.g. 2 to 15 times.

The reaction temperature may influence the end products obtained.Generally it is between 0° and 140° C., although temperatures of ambient(e.g. 20° C.) or more are preferred. When the reagent is MOD suitabletemperatures are 50° to 100° C. When the reagent is an amine suitabletemperatures are 20° to 120° C. When the reaction permits, it isdesirable for the reaction temperature to be below 55° C.

The reaction mixture is preferably stirred throughout the reactionperiod. Although the reaction may occur substantially immediately uponmixing the amine or other reagent with the nitro compound, so thatreaction periods of 1 to 10 minutes may be adequate, preferably longerperiods are used, e.g. 1 to 10 hours, preferably 2 to 5 hours. Routineexperiment will determine the optimum reaction period for any particularreaction temperature since if the reaction is conducted for too long atany particular temperature there is increased risk of unwantedby-products being formed.

When the reagent has the formula MOD, D is preferably aliphatic so theproduct is an ether. D may be lower alkyl, allyl or alkenyl. It may besubstituted, for instance by a second group OM, so that the reagent hasthe formula MODOM, a diether then being formed. The alkali metal M ispreferably sodium but could be, for instance, potassium. The reagent MOD(or MODOM) is preferably formed previously and introduced into thereaction medium in substantially anhydrous form.

Preferably the reagent is a primary or secondary amine. When the reagentis a primary amine it will generate a secondary amino group B while ifit is a secondary amine it will generate a tertiary amino group B. Theprimary or secondary amine reagent can itself be hydrazine or asubstituted hydrazine, thereby generating a hydrazine group.

Broadly, amino reagents used in the invention may have the formula R² R³NH (with the result that B is R² R³ N--) wherein R² may represent --NR⁴R⁵, aryl or aliphatic group, R³, R⁴ and R⁵ may each individuallyrepresent H, aryl or aliphatic groups or R², R³ and the nitrogen atom towhich they are attached may form a heterocyclic ring. When R² representshydrazine then R⁴ at least is preferably hydrogen since this gives theopportunity of two molecules of the compound of formula II reacting withone molecule of the hydrazine. Thus in the end products B may have theformula --N(R³)NR⁵ R⁶ wherein R³ and R⁵ are hydrogen or aliphatic and R⁶is a polycyclic aromatic ring structure such as in Formula I or II, theresultant compound for instance being a symmetrical hydrazinedisubstituted by naphthyl 1,8-imide.

Aliphatic radicals R² to R⁵ or D may be aralkyl, alkyl, cycloalkyl,alkenyl or allyl. They may be short chain, lower, radicals e.g.containing up to 4 carbon atoms but broadly they may contain up to, forinstance, 18 carbon atoms. Any may be substituted by, for instance,carboxylic, sulphonic, phosphate ester, hydroxy or hydroxyalkoxy groups.For instance any of these substituents may carry a recurring alkoxidechain, for instance being obtained by the condensation of ethylene oxideand/or propylene oxide onto a hydroxy alkyl group. Long chain (e.g.C₆₋₁₈) aliphatic groups are preferably highly branched. They may bebenzyl.

Any of the benzene rings in the compounds used as starting materials andmade as end products may contain optional substituents although if thereis a substituent ortho to a nitro group then this substituent should besufficiently small that it does not create steric interference duringthe reaction. Optional substituents that may be present in any ring maybe as described above for R² to R⁵ and may be selected from, forinstance, alkyl, alkoxy, hydroxyalkoxy, cycloalkyl, alkenyl, alkaryl,aryl, hydroxy and halogen. Substituents such as alkyl may themselves besubstituted, for instance, trifluoromethyl. Aryl may be substituted by,for instance, any of the substituents listed but also by solubilisinggroups such as a sulphonic acid group.

The invention can be applied to the production of anthraquinones, namelythe compounds of Formula II. The starting materials, of Formula IIa,generally contain a single nitro group generally in the 1-position butmay contain more than one nitro group. The compounds of Formula IIgenerally contain only one amino group (this being secondary ortertiary) or hydroxy or ether group. The compounds are useful as, forinstance, dyes.

A particularly surprising and important feature of the invention is thediscovery that if a naphthalene ring carries an electron withdrawinggroup A in the 1-position, and preferably also a second group Apreferably in the 8-position, then a 2 or 4 nitro group can be replacedby a group B as defined above under the defined reaction conditions. Theresultant compounds of formula I are useful as dyes, many of them beingfluorescent and many having very useful solubility properties. They maybe used in compositions and for purposes such as those described in U.S.Pat. Nos. 2,953,530 and 3,915,885. Compounds that are not dyes can beused as intermediates for the production of dyes.

The or each electron withdrawing group A can be a cyano group or asulphonic acid group but preferably comprises a carbonyl group, with thecarbonyl group preferably substituted direct onto a ring. The or eachcarbonyl group may be provided by a carboxylic acid group or,preferably, a carboxylic acid salt (generally of sodium or other alkalimetal or a non-interfering amine), an anhydride or an imide group. Whenas is preferred the compound of Formula I is substituted by two groups Ain the 1- and 8-positions these may be present as carboxylic acid orsalt groups or they may be present as a cyclic imide or anhydride withthe 1 and 8 carbon atoms of the naphthalene ring. The radicals providingthe group or groups A may remain unchanged during the reaction or may bereacted to form other radicals. Thus if the starting material of FormulaIa is a 1,8-cyclic imide the end product usually is the same 1,8-cyclicimide, both generally being N-substituted. If the starting material isan anhydride or dicarboxylic acid salt the end product of Formula I maybe a 1,8-cyclic imide, generally N-substituted, or a 1,8-dicarboxylicacid or salt thereof or a 1,8-dicarboxylic anhydride.

Typical reactions according to the invention are illustrated below inwhich for simplicity the naphthalene ring is assumed always to besubstituted in the 4-position by nitro and to be unsubstitutedelsewhere, but of course corresponding reactions also exist for thecorresponding 2-nitro compounds and the compounds in which there areother substituents in the naphthalene ring that do not interfere withthe reaction. In the following reaction schemes R², R³ and D may be asdescribed above and R¹ may be an aliphatic group as described above oramino. ##STR6##

Referring to reaction scheme 1, reaction of the anhydride with a primaryamine results in the formation of an imide, the 4-nitro group remainingunconverted at lower temperatures or being converted to a secondaryamine group at higher temperatures. Preferably R¹ is a straight chainalkyl group. Reaction A occurs best at temperatures of 40° to 140° C.and reaction B at temperatures 0° to 35° C. For instance reaction A maybe conducted at about 50° C. in DMSO or 120° C. in DMF while reaction Bmay be conducted at about 0° C. in DMSO or 20° C. in DMF. Reaction Cadvantageously can be conducted using solvents and temperatures similarto reaction A.

If the anhydride is reacted with a secondary amine then the anhydridering is opened as shown in reaction E to form an amide and salt. If thereaction temperature is low, e.g. 0° to 35° C., the 4-nitro group mayremain unconverted but at higher temperatures, e.g. 40° to 140° C. the4-nitro group is displaced by an amino group, as shown in reaction E.Preferably reaction E is conducted in DMF at temperatures of 80° to 140°C. Further heating of the salt formed in reaction E results inreformation of the anhydride ring, as shown in reaction F. This heatingmay be conducted at 40° to 140° C., preferably 100° to 140° C. Theanhydride can be split open to form the disodium or other alkali metalsalt by treatment with warm alkali, e.g. at 40° to 140° C. preferablyabout 80° C. The resultant disodium salt can be converted to theanhydride by heating with warm mineral acid (e.g. as shown in reaction Nin reaction scheme 2).

The conditions for reaction M in reaction scheme 2 are preferablysimilar to those for reaction A and result in the formation of adisodium salt of the 4-amino substituted compound and this salt can thenbe cyclised to the anhydride by reaction N by warming with a mineralacid, for instance sulphuric or hydrochloric acid, generally at 40° to140° C. preferably about 100° C.

Referring to reaction scheme 3, reaction J is best conducted usingsodium alkoxide at a temperature of 40° to 140° C., preferably 50° to100° C. The solvent must be inert to the reaction conditions and so anether is preferred, preferably diglyme (dimethylether of ethyleneglycol). The product will generally be a ester sodium salt as shown inreaction J and this can be converted to the disodium salt byconventional treatment with sodium hydroxide, as shown in reaction K,e.g. at 40° to 140° C., preferably about 100° C. By adjusting reactionconditions it may be possible to obtain the disodium salt direct. Thedisodium salt can then be converted to the anhydride as in reaction N,and then converted to the imide as in B.

Reaction J can also be conducted starting from the corresponding 4-nitrocyclic imide, instead of anhydride, and whilst this reaction can beconducted to leave the imide unchanged and replace the nitro group by ODthere is a tendency for the imide group to be split and so the yieldsmay be less satisfactory.

All the processes are capable of being operated to give the desired endproducts in good yield and purity. Isolation can be conducted easily,for instance by distilling off the solvent and recrystallising from asuitable liquor, often isopropanol.

Preferred processes according to the invention are processes A and Cabove and comprise reacting a 4-nitro naphthyl compound substituted inthe 1 and 8 positions by carbonyl groups (preferably 4-nitronaphthyl-1,8-anhydride or imide) in the liquid phase in solution and inan aprotic solvent, preferably dimethyl formamide, in the substantialabsence of air and water at a temperature of 40° to 120° C. with atleast 2 moles of an amine of the formula R² R³ NH for a period of 10minutes to 6 hours. This very simple synthesis can easily be operated soas to give a substantially pure product that is eminently suitable foruse in systems such as those described in U.S. Pat. Nos. 2,953,530 and3,915,885 and avoids the problems inherent in all the known processesfor the manufacture of such compounds.

The nitro substituted aromatic compounds are often known compounds andthose that are not known can be made by processes analogous to thoseprocesses that are known for known compounds. For instance, the startingcompound for reaction A may be made by nitration of acenaphthenefollowed by oxidation of this, for example by the general methoddescribed by Mitsuo Okazaki, Tatsuo Tanaka and Setsuro Taniguchi (TokyoInst. Technol)-Yuki Gosei Kagahu Gosei Shi 14, 344-6 (1956). Compoundssuch as the starting material of reaction C may also be made byoxidising 5-nitro acenaphthene to 4-nitro naphthalic anhydride andconverting this to an imide by reacting with the primary amine or withammonia at low temperature for an appropriate period.

The invention may be applied to the production of both new and oldcompounds and an advantage of the invention is that it permits theconvenient production of compounds having much more varied substituentsthan has generally been possible with known methods. For instance1,8-cycloimides of Formula I wherein the imide nitrogen and/or B carry along chain aliphatic hydrocarbon group may be made, the group preferablybeing alkyl and may be branched and/or long chain (e.g. above 10 carbonatoms). Such compounds can have greater oil solubility than the knowncompounds of this formula that are generally available and this can bevery desirable for facilitating the formation of oil based compositionsintended for the same general purposes as described in theaforementioned U.S. Patent Specifications. Accordingly the inventionincludes these novel compounds having increased oil solubility and alsocompositions containing them dissolved in simple oils, such as kerosene,and methods of using them.

Other novel compounds according to the invention are compounds offormula I containing at least one water solubilising group.

One class of novel compounds of the invention are compounds of formulaIII ##STR7## wherein each group A is CO₂ H or an alkali metal, amine orammonium salt thereof or the two groups A together form a carboxylicanhydride group and B is the 2- or 4-position and is OD, where D is H,aryl or an aliphatic group or is a secondary or tertiary amine group--NR² R³ where R² and R³ are as described above, the compound optionallybeing further substituted. Generally B is in the 4-position and is adialkylamino or alkoxy group and there are no further substituents.Generally these compounds are fluorescent and many, especially thoseinvolving water soluble salts of carboxylic acid groups A, are watersoluble.

Other preferred novel compounds are compounds of the Formula IV ##STR8##where B is the group OD or the group --NR² R³ and D, R¹, R² and R³ areas described above and wherein (a) at least one of R¹ and D or (b) atleast one of R¹, R² and R³ comprise a solubilising group containing aprimary amino (NH₂) group or a carboxylic, sulphonate or phosphate estergroup in the form of an alkali metal, amine or ammonium salt or is apolyalkylene oxide group. Many of these also are fluorescent and manyalso are water soluble. Preferably at least one of the groups R¹ and Dor R¹, R² and R³ is a polyoxyalkylene chain, generally of the formula--(CH₂ CH₂ O)_(n) H where n is greater than 1, e.g. 2 to 10, or is agroup --R⁶ X where R⁶ is alkylene, generally of 1 to 4 carbon atomspreferably 1 or 2 carbon atoms and X is a carboxylic, phosphate ester orsulphonate group in the form of an alkali metal, amine or ammonium salt.Preferably R¹ is a solubilising group and there is a second solubilisinggroup in the molecule, generally consisting of D, R² or R³.

Those groups containing alkylene oxide chains may be made byalkoxylation of compounds in which R¹, R², R³ or D is, for instance, ahydroxyalkyl group or where D is a hydroxy group. Those compounds whereR¹, R² or R³ contain a carboxylic, phosphate ester or sulphonate groupcan conveniently be made by one of the reactions illustrated above usingan appropriately substituted amine, for example taurine or glycine inthe form of their sodium salts.

The following are some examples of the invention.

EXAMPLE 1

4-Nitronaphthalic anhydride is prepared from acenaphthene by the methoddescribed by Okazaki et al (see above) involving nitration ofacenaphthene, oxidation to 4-nitronaphthalic acid and heating of theacid at 120° C. for 4 hours to give 4-nitronaphthalic anhydride.

4-Nitronaphthalic anhydride is dissolved in the minimum of dimethylsulphoxide (D.M.S.O.). Methylamine is added in the ratio of 9 moles ofamine per mole of anhydride. Addition of amine and subsequent stirringis carried out at 50° C. in the absence of air by passing nitrogenslowly through the reaction vessel so that the pressure of nitrogen inthe apparatus is greater than atmospheric pressure. The reaction mixtureis stirred at ambient temperature for 3-4 hours, although the reactionappears to be virtually instantaneous. D.M.S.O. is removed under areduced pressure by distillation (60° C. and 1 mmHg pressure) withpassage of nitrogen through the distillation apparatus to act as a"leak". The solid remaining when distillation was complete was a mixtureof two or more components which were separated by column chromatographyusing silica gel (70-230 mesh) as the absorbent and an 80/20% mixture ofchloroform and ethyl acetate as the eluent. The major componentseparated is 4-methylamino-N-methylnaphthyl-1,8-imide. This was found tohave a melting point of 261° to 262° C. (literature 258° to 260° C.) andan analysis C69.0%, H5.08% and N11.3% (theoretical C70.0%, H5.0%,N11.6%). The infrared, proton nuclear magnetic resonance and UV spectrawere obtained and confirmed the structure. The product was obtained in71% yield, based on 4-nitronaphthalic anhydride.

As will be apparent, this is an example of reaction A from reactionscheme 1.

Instead of isolating in the described manner, isolation can also beconducted by distilling off the solvent and crystallising the residuefrom isopropanol.

A similar process can be conducted under broadly similar conditions togive end products as shown in reaction scheme 1, such end products beingsubstituted in the 4-position by an amino group --NR² R³ and, whenappropriate, on the imide nitrogen by R¹. In every instance the protonnuclear magnetic resonance, infrared and ultraviolet spectra were asexpected and the elemental analysis was substantially accurate. Theconditions and results are summarized in Table 1.

                  TABLE 1                                                         ______________________________________                                        Experiment                                                                            Reaction          Temp   Duration                                                                             Moles                                 No.     Route    Solvent  (°C.)                                                                         (hours)                                                                              amine                                 ______________________________________                                        1       A        DMF      120    5      9                                     2       A        DMF      120    5      9                                     3       A        DMSO      50    4      9                                     4       A        DMSO      50    4      9                                      5a     B        DMSO     0      3      5                                      5b     C        DMSO      20    3      5                                      6a     B        DMSO     0      3      5                                      6b     C        DMSO      20    3      5                                      7a     E        DMF      120    3      5                                      7b     F        DMF      120    3      5                                     8       A        DMF      100    3      5                                     9       A        DMF       80    5      5                                      10     A        DMF       80    5      5                                     ______________________________________                                                                             m.p. (°C.)                        Experiment                           end                                      No.     R.sup.1     R.sup.2                                                                              R.sup.3   product                                  ______________________________________                                        1       CH.sub.3    H      CH.sub.3  261-262                                  2       nC.sub.4 H.sub.9                                                                          H      nC.sub.4 H.sub.9                                                                        127-128                                  3       nC.sub.6 H.sub.13                                                                         H      nC.sub.6 H.sub.13                                                                       90-91                                    4       nC.sub.10 H.sub.21                                                                        H      nC.sub.10 H.sub.21                                                                      93-95                                     5a     nC.sub.4 H.sub.9                                                                          --     --        --                                        5b     nC.sub. 4 H.sub.9                                                                         H      nC.sub.10 H.sub.21                                                                      109-110                                   6a     nC.sub.4 H.sub.9                                                                          --     --        --                                        6b     nC.sub.4 H.sub.9                                                                          C.sub.2 H.sub.5                                                                      C.sub.2 H.sub.5                                                                         orange oil                                7a     --          C.sub.2 H.sub.5                                                                      C.sub.2 H.sub.5                                                                         118-120                                   7b     --          C.sub.2 H.sub.5                                                                      C.sub.2 H.sub.5                                                                         190-192                                  8       CH.sub.2 CH.sub.2 SO.sub.2 Na                                                             H      CH.sub.2 CH.sub.2 SO.sub.2 Na                                                           >360;                                    9       NH.sub.2    H      NH.sub.2  >360;                                     10     CH.sub.2 CO.sub.2 Na                                                                      H      CH.sub.2 CO.sub.2 Na                                                                    >360;                                    ______________________________________                                    

The products of Experiments 8, 9 and 10 were water soluble. The productof Experiment 8 gave a yellow solution having absorption maxima at 210and 430 nm. The product of Experiment 9 gave a green solution havingabsorption maxima at 284 and 400 nm. The product of Experiment 10 gave agreen solution having absorption maximat at 323 nm.

EXAMPLE 2

A process similar to Experiment 2 of Example 1 was conducted using thesolvent, temperature, reaction route, and duration as in Experiment 2but using 9 moles amine per mole nitro starting compound and using2-nitronaphthalic anhydride as the starting material. The resultant2-butylamino-N-butylnaphthyl-1,8-imide gave a green/yellow solutionhaving absorption maxima at 287, 323, 394 and 440 nm.

EXAMPLE 3

Reaction scheme 3 was conducted by reacting 4-nitrophthalic anhydridewith 5 moles sodium ethoxide for 5 hours at 80° C. in diglyme assolvent. The resultant product was a yellow/brown solid having ananalysis consistent with the 4-ethoxy substituted ethyl ester sodiumsalt and could be converted to the disodium salt by reaction withcaustic soda and to 4-ethoxynaphthalic anhydride by treatment with warmhydrochloric acid.

EXAMPLE 4

1-Nitroanthraquinone was reacted in DMF at 20° C. with 5 molesn-butylamine for 5 hours. The reaction produced 1-butylaminoanthraquinone which was a deep red solid having a melting point of 78°to 79° C.

EXAMPLE 5

To demonstrate the desirability of eliminating air from the mixture,4-nitronaphthalic anhydride was reacted with n-butylamine in DMSO at150° C. without exclusion of air. Although the expected di-n-butyl imidewas produced a large number of by-products were simultaneously producedwhich could not be easily removed.

We claim:
 1. A process for producing a compound of Formula I ##STR9##from a compound of formula Ia ##STR10## wherein, in each of Formula Iand Formula Ia, each substituent A contains a carbonyl group substituteddirect into the ring and the two substituents A may be linked to form acyclic group with the carbon atoms to which they are attached and thegroups B and NO₂ are each in the same position and are in a positionselected from the 2 and 4 positions and, in Formula I, B is selectedfrom secondary and tertiary amino groups, the process comprisingreacting the compound of Formula Ia in a substantially anhydrousreaction medium containing a solvent with at least a stoichiometricamount of a reagent selected from organic primary and secondary amines.2. A process according to claim 1 in which the solvent is an aproticsolvent.
 3. A process according to claim 1 in which the reaction isconducted in the substantial absence of oxygen.
 4. A process accordingto claim 1 in which the reaction is conducted at a temperature between0° C. and 140° C. in the substantial absence of oxygen and in thepresence of an aprotic solvent.
 5. A process according to claim 4 inwhich the reaction is conducted at a temperature of from 20° to 120° C.6. A process according to claim 1 or claim 4 in which the groups A inthe compound of Formula Ia together with the carbon atoms to which theyare attached form an imide or an anhydride ring.
 7. A process accordingto claim 1 for making a 4-N-substituted amino N-substitutednaphthyl-1,8-imide comprising reacting a 4-nitronaphthyl-1,8-imide oranhydride in solution in dimethylformamide in the substantial absence ofoxygen or water at a temperature of 40° to 120° C. with a primary aminefor a period of 10 minutes to 6 hours.
 8. A process according to claim 1or claim 4 in which the amount of reagent is from 2 to 15 times thestoichiometric amount.
 9. A process according to claim 1 or claim 4 inwhich the reagent is a primary or secondary aliphatic amine and thegroups A in the compound of Formula Ia, together with the carbon atomsto which they are attached, form an anhydride or imide ring.
 10. Aprocess according to claim 1 or claim 4 in which the reagent is primaryaliphatic amine, in the compound of Formula Ia the groups A togetherwith the carbon atoms to which they are attached form an anhydride ringand, in the compound of Formula I, the groups A together with the carbonatom to which they are attached, form an N-substituted imide ring and Bis a substituted amino group.
 11. A process according to claim 1 orclaim 4 in which the solvent is dimethyl formamide.